eris-keys/node_modules/ramda/src/takeLastWhile.js

a JavaScript client library for eris-keys

var _curry2 = require('./internal/_curry2');


/**
 * Returns a new list containing the last `n` elements of a given list, passing
 * each value to the supplied predicate function, and terminating when the
 * predicate function returns `false`. Excludes the element that caused the
 * predicate function to fail. The predicate function is passed one argument:
 * *(value)*.
 *
 * @func
 * @memberOf R
 * @since v0.16.0
 * @category List
 * @sig (a -> Boolean) -> [a] -> [a]
 * @param {Function} fn The function called per iteration.
 * @param {Array} list The collection to iterate over.
 * @return {Array} A new array.
 * @see R.dropLastWhile, R.addIndex
 * @example
 *
 *      var isNotOne = x => x !== 1;
 *
 *      R.takeLastWhile(isNotOne, [1, 2, 3, 4]); //=> [2, 3, 4]
 */
module.exports = _curry2(function takeLastWhile(fn, list) {
  var idx = list.length - 1;
  while (idx >= 0 && fn(list[idx])) {
    idx -= 1;
  }
  return Array.prototype.slice.call(list, idx + 1);
});